service ISUZU TROOPER 1998 Service Workshop Manual

SERVICE INFORMATION 00 Ð 35
MAGNETIC CLUTCH DOES NOT RUN
·TURN THE STARTER SWITCH ON AND START THE
ENGINE.
·TURN THE FAN SWITCH ON.
·DOES THE BLOWER MOTOR RUN?
YESNO
REFER TO THE DIAGNOSIS PROCEDURE FOR
ÒBLOWER MOTOR DOES NOT RUNÓ.·IS THE FUSE C-20 (10A) NORMAL?
YESNO
REPLACE THE FUSE.·DISCONNECT THE A/C SWITCH CONNECTOR AND
REMOVE THE A/C SWITCH.
·IS THE A/C SWITCH NORMAL?
YESNO
YESNO
REPAIR AN OPEN CIRCUIT BETWEEN THE
FUSE C-20 AND I23-2.·REINSTALL THE A/C SWITCH AND DISCONNECT THE DUAL
PRESSURE SWITCH (OR TRIPLE PRESSURE SWITCH) CON-
NECTOR C25.
·TURN THE A/C SWITCH ON.
·IS THE BATTERY VOLTAGE APPLIED AT HARNESS SIDE
CONNECTOR C25-1?
YESNO
REPLACE THE SWITCH.·RECONNECT THE CONNECTOR C25 AND DISCONNECT THE
A/C THERMO RELAY CONNECTOR X5.
·IS THERE CONTINUITY BETWEEN HARNESS SIDE CONNEC-
TOR C25-2 AND X5-1?
YESNO
REPAIR AN OPEN CIRCUIT BETWEEN I23-6
AND C25-1.·IS THE DUAL PRESSURE SWITCH (OR TRIPLE PRESSURE
SWITCH) NORMAL?
YESNO
REPAIR OR REPLACE THE SWITCH.·IS THE BATTERY VOLTAGE APPLIED AT HARNESS SIDE
CONNECTOR I23-2?

00 Ð 36 SERVICE INFORMATION
·IS THE BATTERY VOLTAGE APPLIED AT HARNESS SIDE
CONNECTOR X5-2?REPAIR AN OPEN CIRCUIT.
YESNO
·IS THE A/C THERMO RELAY NORMAL?REPAIR AN OPEN CIRCUIT BETWEEN THE
FUSE C-20 AND X5-2.
YESNO
·DISCONNECT THE ELECTRONIC THERMOSTAT CONNEC-
TOR I42.
·IS THE BATTERY VOLTAGE APPLIED AT HARNESS SIDE
CONNECTOR I42-3?
YESNO
·IS THERE CONTINUITY BETWEEN HARNESS SIDE CON-
NECTOR X5-3 AND I42-1?REPAIR AN OPEN CIRCUIT BETWEEN I23-6
AND I42-3.
YESNO
REPAIR AN OPEN CIRCUIT.
YESNO
·IS THERE CONTINUITY BETWEEN HARNESS SIDE CON-
NECTOR I42-2 AND THE GROUND?REPAIR AN OPEN CIRCUIT.
REPLACE THE RELAY.
·DIS CONNECT THE MAGNETIC CLUTCH CONNECTOR E27.
·CONNECT THE BATTERY WITH MAGNETIC CLUTCH SIDE
CONNECTOR E27-1.
·DOES THE MAGNETIC CLUTCH.
YESNO
REPAIR OR REPLACE THE MAGNETIC CLUTCH.·REPAIR AN OPEN CIRCUIT BETWEEN X5-4 AND E27-1.

SERVICE INFORMATION 00 Ð 37
CONDENSER FAN
When the cycling switch, which controls the
condenser fan of the triple pressure switch while
the A/C switch is on, senses the refrigerant pressureand the condenser fan turns on, the motor operates
via the condenser fan relay.
123
45 6
4
13
24
1
FAN SW.
B-2
OFF
I-18
I-18
B-1
(LHD)
(RHD)
X-19
1
3
4
5
RELAY;
CONDENSER
FAN
4TRIPLE
PRESSURE
SWITCH
3
1CONDENSER
FAN
2M
C-75 C-39
C-25
FL-4
30A
CONDENSER FANFL-1
80A
MAIN
2
6
1
I-23
RELAY; A/C
A/C SWITCH
2
C-39C-75C-25
I-23X-19
123 4
567 843
872
61
5
121 21
2 34
213
5 4612
34
D08RWD70

00 Ð 38 SERVICE INFORMATION
CONDENSER FAN DOES NOT RUN
YESNO
·DOES A/C SYSTEM OPERATE CORRECTLY?
·IS FL-4 (30A) FUSE OK?CHECK A/C SYSTEM AND REPAIR AS NECESSARY
YESNO
·IS CONDENSER FAN RELAY (X-19) OK?REPLACE
REPLACE
YESNO
·IS TRIPLE PRESSURE SWITCH (CYCLING SWITCH SIDE)
OK?
REPLACE
YESNO
·IS CONDENSER FAN MOTOR OK?
REPLACE
YESNO
·CHECK TO SEE IF CONTINUITY BETWEEN FL-4 (30A)
FUSE AND CHASSIS SIDE RELAY TERMINAL NO. X19-1.
REPLACE
YESNO
·CHECK TO SEE IF CONTINUITY BETWEEN CHASSIS SIDE
CONNECTOR TERMINAL NO. I23-6 AND NO. C25-3.
OPEN CIRCUIT
YESNO
·CHECK TO SEE IF CONTINUITY BETWEEN CHASSIS SIDE
CONNECTOR TERMINAL NO. C25-4 AND CHASSIS SIDE
RELAY TERMINAL NO. X19-4.
OPEN CIRCUIT
YESNO
·CHECK TO SEE IF CONTINUITY BETWEEN CHASSIS SIDE
RELAY TERMINAL NO. X19-5 AND CHASSIS SIDE
CONNECTOR TERMINAL NO. I18-4.
OPEN CIRCUIT
YESNO

SERVICE INFORMATION 00 Ð 39
·CHECK TO SEE IF CONTINUITY BETWEEN CHASSIS SIDE
RELAY TERMINAL NO. X19-3 AND CHASSIS SIDE
CONNECTOR TERMINAL NO. C75-1.
YESNO
OPEN CIRCUITPOOR GROUND OR OPEN CIRCUIT BETWEEN CHASSIS
SIDE CONNECTOR TERMINAL NO. C75-2 AND BODY
GROUND (NO. C39-7)
CONDENSER FAN DOES NOT STOP
·IS CONDENSER FAN RELAY (X-19) OK?
YESNO
REPLACETRIPLE PRESSURE SWITCH (CYCLING SWITCH SIDE)
DEFECTIVE
REPLACE TRIPLE PRESSURE SWITCH

00 Ð 40 SERVICE INFORMATION
1. Defective rotor/piston
2. Defective bearing (DKS-15CH)
3. Defective shaft
1. Defective bearing
2. Defective clutch
3. Clearance between drive plate
and pulley not standard
1. Defective gasket
2. Defective rotor/reed valve
3. Defective trigger valve/suction
valve
1. Defective rotor/piston
2. Defective shaft
3. Rotating parts seized due to
insufficient oil
1. Defective seal
2. Defective O-ringReplace compressor/cylinder and
shaft assembly
Replace cylinder and shaft assembly
Replace compressor/cylinder and
shaft assembly
Replace magnetic clutch
Replace magnetic clutch
Adjust the clearance or replace
magnetic clutch
Replace compressor/gasket
Replace compressor/valve plate
Replace compressor/suction valve
Replace compressor/cylinder and
shaft assembly
Replace compressor/cylinder and
shaft assembly
Replace compressor
Replace compressor/shaft seal
Replace Noise from compressor
Noise from magnetic
clutch face
Insufficient cooling
Not rotating
Oil and/or gas leakage 1
2
3
4
5
ITEM PROBLEM POSSIBLE CAUSES CORRECTION
COMPRESSOR TROUBLESHOOTING

SERVICE INFORMATION 00 Ð 41
I-18 I-23
123456126
OFF
1
FAN SW. 2
3
4
OFF
A/C SW.
ON
FAN CONTROL KNOB (FAN SWITCH) AND A/C
SWITCH
INDIVIDUAL INSPECTION
Check for continuity between fan switch and A/C switch
side connector terminals.
2
65 4 31362
51
4

I-23I-18
I-23I-18
5
A/C SW. BEZEL
ILLUMI-
NATION
FAN SW. OFF1
2
3
4 32 6 1253641
HEATER & A/C, THERMOSTAT, COMPRESSOR,
CONDENSER FAN AND CERAMIC HEATER RELAY
Check for continuity between the relay terminals.
2Ð 4..... No continuity
(When battery voltage is applied between 1Ð 3)
2Ð 4..... Continuity
2
2
1
144
3
3
Terminal
No. SW.
position
DUAL PRESSURE SWITCH
21
Disconnect pressure switch connector and check for
continuity between pressure switch side connector
terminals.

00 Ð 42 SERVICE INFORMATION
TRIPLE PRESSURE SWITCH (W/CONDENSER FAN)
43
12
1) Disconnect the connector and check for continuity
between pressure switch side connector terminal.
2) Reconnect the connector to activate the A/C switch,
and check to see if there is continuity between the
chassis side connectors and the fan operates.
[A/C OFF]
[A/C ON]
Terminal No. Control Continuity
1- 2Magnetic Clutch Continuity
3- 4Condenser Fan No Continuity
Terminal
Refrigerant Pressure Continuity Fan
No.
1079±98 kPa No
OFF
(11.0±1.0 kgácm
2/ 156±14 psi) Continuity
3- 4
1471±98 kPa
Continuity ON
(15.0±1.0 kgácm
2/ 213±14 psi)
BLOWER MOTOR
1
2
1) Disconnect the blower motor (B-5) connector from
the blower motor.
2) Connect the battery positive terminal to the No. 1
(NO.2; RHD) terminal of the blower motor and
negative to the No. 2 (NO. 1; RHD).
3) Be sure to check to see if the blower motor operates
correctly.
Terminal Normal
SW. No.12346Operating
position Resistance
2.4W
0.90W
0.28W
Ð 1
2
3
4
RESISTOR
14263
2
Motor3641
432
(SW.position) (Connector
terminal)
1
1) Disconnect resistor (I-41) connector.
2) Check for continuity and resistance between the
terminals of the resistor.

SERVICE INFORMATION 00 Ð 43
CONDENSER FAN
1 2
THERMO SWITCH (ENGINE)
1 2
1) Disconnect the condenser fan connector (C-75).
2) Connect the battery positive terminal to the No. 1
terminal and negative to No. 2.
3) Be sure to check to see if condenser fan operates
correctly.
With the environmental temperature of the switch set to
the following conditions, check to see if there is any
continuity between the switch side connector terminals.
Ambient Terminal
Continuity
Temperature No.
Above 77 Ð 83°C
1Ð 2No Continuity
(170.6Ð181.4°F)
CERAMIC HEATER
1
2
Ceramic heater
Disconnect the ceramic heater connector and check for
continuity between ceramic heater side connector
terminals.
Connector No. B-48
Terminal 1 2
Continuity

00 Ð 44 SERVICE INFORMATION
FULL HOT SWITCH
21
Temperature
control link
Full hot switch
1) With the temperature control knob set to the full hot
position, check to see visually if the temperature
control link of the heater unit operate correctly and if
the link contacts securely with the full hot switch.
2) Disconnect the full hot switch connector.
3) With the full hot switch contacted, check to see if
there is any continuity between the switch side
connector terminals.
B-49
Terminal
Full No. 1 2
hot switch
FREE
CONTACT